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07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Nematic liquid crystals in a spatially step-wise magnetic field
Gaetano Napoli1, Michele Scaraggi1
1Dipartimento di Ingegneria dell'Innovazione, Università del Salento, via per Monteroni, Edificio "Corpo O", 73100 Lecce, Italy.
Physical Review. E
|February 13, 2016
Summary
We investigated molecular reorientation in nematic liquid crystals (nLC) using textured magnetic fields. This research paves the way for advanced tribotronic applications by controlling nLC textures.
Area of Science:
- Soft Matter Physics
- Materials Science
Background:
- Nematic liquid crystals (nLC) exhibit unique anisotropic properties.
- External fields can induce molecular reorientation in nLCs.
- Controlling nLC texture is key for advanced applications.
Purpose of the Study:
- To investigate molecular reorientation in nLCs induced by textured magnetic fields.
- To analyze the field-induced splay-bend Fréedericksz transition.
- To explore the potential of nLC texturing for tribotronic applications.
Main Methods:
- Utilized Frank's continuum theory with perturbation analysis.
- Employed a finite differences method for nonlinear equations.
- Applied analytic approaches for bulk director profiles at high fields.
- Incorporated Bruggeman texture hydrodynamics theory.
Main Results:
- Detailed analysis of the field-induced splay-bend Fréedericksz transition.
- Derived analytic solutions for bulk director profiles using elliptic integrals.
- Qualitatively discussed nLC director configurations for friction regulation.
Conclusions:
- Demonstrated control over nLC molecular reorientation using textured fields.
- Established a pathway for highly controlled nLC texturing.
- Highlighted potential applications in tribotronics for active friction control.
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